This application relates generally to a pneumatic tool. More particularly, this application relates to a pneumatic tool which can be selectively operated in either a muffled mode or an unmuffled mode.
Pneumatic tools are driven by pneumatic motors which rely on the flow of compressed gas through vanes in order to provide power. Once compressed gas has been utilized by the motor, it must be exhausted from the motor and the tool so that a constant flow of gas can be maintained.
Typically, the velocity of the exhaust gas is quite high, generating a loud noise as it leaves the pneumatic tool. In order to reduce the noise, muffler mechanisms have been developed to reduce the velocity of the compressed gas as it escapes from the pneumatic tool. By slowing the velocity of the compressed gas, the noise level is reduced.
Reducing the velocity of the compressed gas is typically achieved by inserting muffler material along the exhaust path for the compressed gas. The muffler material provides resistance to the flow of compressed gas, thereby reducing its velocity and reducing the noise generated. However, by inserting muffler material within the flow path of the compressed gas, back pressure is created which reduces the flow of gas through the motor, reducing the power of the pneumatic tool.
Consequently, a typical pneumatic tool will offer its user either high power with high noise level in an unmuffled exhaust system, or reduced noise but reduced power in a muffled exhaust system.
Therefore, it is a general object of this application to provide a pneumatic powered tool that avoids the disadvantages of prior designs while affording additional structural and operating advantages.
An important feature is the provision of a pneumatic tool which is capable of working in either a muffled mode of operation or a higher power, unmuffled mode of operation.
Another important feature is the provision of a pneumatic tool which is easily switchable between a muffled mode of operation or an unmuffled mode of operation.